I am by no means a hardcore Destiny player. Since I don't have a regular group that also plays (and little energy/time to try to find one), I haven't done the serious endgame content like raids or most of the other content that doesn't automatically match you with other players. I do have a character at the highest possible level, but that's about it.

I'm going to start with a summary of what Destiny is to lay the groundwork for understanding what is changing with the expansion. This will try to hit the highlights; it is not intended to be comprehensive.

What is Destiny?

Destiny is a first-person shooter that has some elements similar to massively-multiplayer online games (MMOs, like World of Warcraft. It can be played by yourself, cooperatively with a few other players, or competitively with teams of players facing each other. When you play by yourself or cooperatively, you are completing missions or scenarios against computer opponents (called player-versus-environment modes, or PvE). Competitive modes are called player-versus-player, or PvP.

You can play all this content with the same character (each player account can have up to three characters), and progress with your character carries across the different game modes. The different game modes are represented in the game as different destinations you can travel to. There are also destinations that act as social hubs where you can interact with computer-controlled vendors to get various equipment and items. You can also start and complete various other tasks, like quests, at the social hubs.

Classes

There are three character classes in Destiny - once you make this choice, you cannot change it. The classes are Titan, Warlock, and Hunter. The classes play differently because they all have different specialized abilities as well as somewhat different base strengths and weaknesses. I won't get into the particulars here, though.

Each class also has two subclass options. For example, the Titan can be either a Striker or a Defender. The Striker's signature ability ("special") is smashing the ground to cause an area-of-effect attack. The Defender's special ability is creating a shield around a small area which prevents attacks from going through. You can switch sub-classes at pretty much any time.

All the characters use the same types of weapons, though, so the basic mechanics of jumping around and shooting enemies is pretty similar across the different classes.

You also customize your character by picking one of three species, selecting whether it is male or female, and choosing among various cosmetic options. None of these choices have a direct effect on how the character plays.

Character progression

When you start a new character, it begins at level 1, meaning that you have relatively few abilities available to you at the start of the game and you are relatively weak. Like an MMO (or basically any roleplaying game), you gather experience by killing enemies and completing tasks, which eventually allows you to level up. Leveling up means that you can take on harder enemies - if your level is a few levels below that of your enemies, you will do little damage to them, and they will hit you like a freeway-load of trucks.

Gaining experience also slowly unlocks your various abilities. So, eventually you will be able to throw a grenade, and then activate your super ability, and so on. Later abilities let you do things like add a new effect to your existing super ability, or change the type of grenade you throw.

Also like an MMO, you can enhance your character by using better equipment (armor and weapons). Some equipment can't be used until you reach a particular level, especially early in the game. Better weapons intrinsically do more damage. Better armor provides more intrinsic defense and also improves your other attributes. I won't go into much detail about those attributes, but they basically let you use your abilities (throwing grenades, using the special, and performing a particular type of melee attack) more frequently.

In the current game, you continue to gain experience until you reach level 20. After that, you gain additional levels by equipping items that have an attribute called Light. All the Light from the equipment that you are currently using is added up to determine your level. In the current game (with the second expansion), the highest level you reach by equipping items with Light is level 34. This mechanic is similar to how in MMOs you can get better tiers of equipment while still remaining at the level cap (maximum available level), but it's a little different in how the gear you wear explicitly determines your level.

Still, experience doesn't go away entirely past Level 20. Your guns and armor pieces also have abilities that can be unlocked by accumulating experience (just like your character's abilities). These abilities are things like faster reload speed for a weapon, or carrying more of a particular type of ammo for an armor piece. The abilities are tied to the particular equipment, so you only receive the benefit when the item is equipped.

Hey, are we ever going to talk about the new expansion?

Sorry it's taking a while, and I hope the terminology has not been too confusing so far. We're just trying to establish the context for understanding what's changed.

Here we go; onto the new stuff.

New sub-classes

Each of the character classes will get a new sub-class that they can switch to, and those sub-classes each have brand-new abilities. They should theoretically open up some new styles of play. This could be refreshing for long-term players, and it could provide some new niches that may be more appealing to certain players than any of the older options. We'll see how they play when the expansion comes out. At a minimum, it adds novelty.

Changes to character progression in The Taken King

In the new expansion, your character's level will be entirely determined by how much experience you've gained — it will no longer depend on the gear that you are wearing. Gear will still determine your amount of Light, which does affect how powerful your character is, but now a character's Light will be the average of the attack/defense values of all your equipped guns and armor. They are also making a couple of other equipment slots contribute this overall average that were mostly cosmetic before.

In some sense, this makes things more complicated. Before, you could look at one number (your character's level) and have a sense for what kind of content you could handle.

However, this also meant you had to get high-level gear to feel like you made full progress on your character. With the new expansion, you can get to the maximum level just by playing the game, regardless of what gear you happen to get. You still can't do the hardest types of content without better gear, but that is no different than before. And now, when the level cap is increased, you'll be at the same starting point as everyone else, as long as you played enough to get the necessary experience.

Here's an explanation that may or may not help with understanding the difference - this move sort of changes things from a one-dimensional progression to a two-dimensional one. Before, everyone fell somewhere along the same line, with max level at the end of the line. You couldn't get past certain points on that line without getting better gear. Now, everyone can get to the end of the line just by earning experience. Gear matters, though, because it helps you go further in a new direction. It doesn't move you further along the line, but now your character can go deeper instead of just going forward. And you need to go deep enough in this new direction to tackle high-end, hard content.

Again, this is more the model that MMOs use. In those games (or at least in World of Warcraft, which I'm most familiar with), everyone can get to the maximum level by getting experience, but getting better gear allows you to do enough damage (and withstand enough damage) to complete more advanced endgame content.

I heard you can immediately get one character to level 25 in the expansion?

Yes, the expansion gives you a token that can be redeemed to get you to level 25 right away. I don't think this is necessarily the best for a player totally new to Destiny. Destiny slowly unlocks content as you level from 1 to 20. It would probably be overwhelming for a new player to get that all at once.

However, I think the "skip to level 25" feature is good for a few scenarios. If you have friends who play Destiny and you want to start playing with them right away, this could be a good way to catch up quickly. But now you'll be relying on those friends to explain more of the game to you, rather than letting the game itself do that.

The other reason I can imagine using that token is if you've played Destiny more casually and have run through most of the base missions, but haven't quite gotten to level 25 (maybe you're at 18 or 20 or so, and don't know the fastest path to getting the gear that will take you to 25). The token gives you a bit of a boost toward seeing brand-new stuff faster.

Making your weapons better

One complaint players had with earlier expansions is that new weapons made their old favorites obsolete. Coming into Destiny with MMO experience, I was kind of used to that, but people (including myself) do get attached to particular equipment that you use a lot and invest a lot of effort into. So, in the expansion, you'll be able to improve an existing weapon by essentially sacrificing a weapon with better stats (along with some other materials, too).

For example, if your favorite rifle has an attack value of 170, and you find a new rifle with an attack value of 180, you can raise the attack value of your favorite to something like 178 if you're willing to destroy the new one in the process (those numbers are made up; I don't know the specific formula for the process). This way, you can keep using weapons you like without them becoming ineffective.

Questing and bounties

Bungie found that people liked doing some of the longer quest chains in the first year --- it gave a sense of really accomplishing something and often got players involved in new aspects of the game. For example, I pretty much hated Destiny PvP before I got a quest where I had to get loads of PvP kills to move on - oh, and dying too much made you lose progress. This forced me to play lots of PvP matches, which meant I saw maps over and over again, and learned what kinds of behaviors got me killed faster and which ones let me collect more kills. It honestly just led me to practice PvP enough to get the competence I needed to enjoy and appreciate that type of play. Now, I actually like playing PvP (most of the time).

Anyway, quests are good and feel good to complete, so in The Taken King there will (1) be more of them, (2) be interface improvements that make tracking and turning them in easier, and (3) be better rewards for doing them. Bungie is also using quests (and bounties, which are like shorter, repeatable quests) to give players an avenue toward guaranteed rewards. Usually, you get a new armor piece or gun by either killing an enemy that randomly dropped it, or by being randomly given it at the end of a mission or PvP match. This is entirely unpredictable and undependable, so it can be very frustrating when you don't get anything you need for long stretches of time. Instead, quests in the expansion have guaranteed rewards, so you can embark on a set of activities with the confidence that it will pay off at the end.

Exotics

An Exotic weapon or piece of armor is a rare item that often has specialized abilities and is generally quite powerful relative to other equipment. Because of that, you can have at most one Exotic weapon and one Exotic armor equipped at any time. Players love Exotics and work hard to get them, but they were not sure what would happen to these hard-earned items in the expansion.

In The Taken King, some of these Exotics will have new and improved versions (with a different appearance, as well). If you have the old version of the Exotic, you can automatically buy the new version, too. Yay, better weapons and armor! You can also buy the old versions of the Exotics, too, as long as you found it at least once (so now you can get an Exotic back if you dismantled your first one).

Currency

I've mentioned buying things a couple of times. There are a variety of currencies and materials in Destiny that are spent at vendors and used to upgrade equipment. I'm not going to get into all of them, but in the original game there was one major type of currency that was associated with PvE-focused vendors (and earned by PvE activities) and another type that was PvP-focused (and earned by PvP activities). In the expansion, these two are essentially merging into one currency that is used everywhere. This currency will also be shared across all your characters, which is nice; a lot of times before you ended up with a bunch of the old currency stockpiling on your most advanced character, when it would be nice to use that to improve your other, lower-level characters.

Also, in the current game you can only earn 100 of each type of the old currencies in a week, and hold at most 200 at a time. In the expansion, you'll still only be able to hold up to 200 of the new unified currency, but there are no limits on earning it. The more you play, the more you earn, as long as you keep spending it, too.

Storage space

The place you keep gear and materials you aren't using is called the Vault (not to be confused with the raid called the Vault of Glass). In the expansion, you'll have twice as much space to store weapons and more than twice as much space to store armor. People seem super-pumped about this. Like, kind of surprisingly so. At least I am surprised by the degree of enthusiasm for storage space.

Factions

Destiny has several factions that you need to earn reputation with before they will let you buy things from them. The way you earned this was by doing certain kinds of tasks while wearing a certain piece of equipment associated with that faction. Now, you just ask the faction for a badge to earn reputation with them. You can change factions once per week. Simpler!

Wrap-Up

I certainly have not covered all the expansion-related changes, but I hope this gives a more Destiny-naive reader a better sense of what is coming and why Destiny players care about it.

Will these changes help brand-new players? I'm not sure. I think they are making some quest-oriented changes to the early missions, so we will have to see if that early experience is more streamlined and does a better job at teaching the various aspects of Destiny. Destiny is a pretty sprawling game — not so much in the size of the world, exactly, but more in the number of different things you can do (well, relatively different; you're pretty much always shooting something with a gun), and the number of different avenues for improving and customizing your character. Just playing Destiny a lot is pretty much how you get familiar with those things.

However, I do think that these changes will make Destiny more pleasant and more fun for players as they accumulate that experience, and potentially smooth enough of the rough edges that could cause players to lose interest and motivation in the game. I would say that the changes are pretty much geared toward the "casual" Destiny player, but a "casual" Destiny player is still probably a player with quite a high willingness to push through a lot of stuff in their way. We'll have to see how it turns out when it launches — I am certainly looking forward to it.